The total fertility rate in the United States estimated for 2014 is 1.86 children per woman,[6][7] which is below the replacement fertility rate of approximately 2.1. Compared to other Western countries, in 2012, U.S. fertility rate was lower than that of France (2.01),[8]Australia (1.93) and the United Kingdom (1.92).[9] However, U.S. population growth is among the highest in industrialized countries,[10] because the differences in fertility rates are less than the differences in immigration levels, which are higher in the U.S.[11][12] The United States Census Bureau shows population increase of 0.75% for the twelve-month period ending in July 2012. Though high by industrialized country standards, this is below the world average annual rate of 1.1%.[10]

There were over 158.6 million women in the United States in 2009. The number of men was 151.4 million. At age 85 and older, there were more than twice as many women as men. People under 20 years of age made up over a quarter of the U.S. population (27.3%), and people age 65 and over made up one-eighth (12.8%) in 2009.[13] The national median age was 36.8 years.[13]

The United States Census Bureau defines White people as those "having origins in any of the original peoples of Europe, the Middle East, or North Africa. It includes people who reported "White" or wrote in entries such as Irish, German, Italian, Lebanese, Near Easterner, Arab, or Polish."[14] Whites constitute the majority of the U.S. population, with a total of about 245,532,000 or 77.7% of the population as of 2013. There are 62.6% Whites when Hispanics who describe themselves as "white" are taken out of the calculation. Despite major changes due to illegal and legal immigration since the 1960s and the higher birth-rates of nonwhites, the overall current majority of American citizens are still white, and English-speaking, though regional differences exist.

The American population almost quadrupled during the 20th century—at a growth rate of about 1.3% a year—from about 76 million in 1900 to 281 million in 2000. It reached the 200 million mark in 1968, and the 300 million mark on October 17, 2006.[15][16] Population growth is fastest among minorities as a whole, and according to the Census Bureau's estimation for 2012, 50.4% of American children under the age of 1 belonged to minority groups.[17]

Hispanic and Latino Americans accounted for 48% of the national population growth of 2.9 million between July 1, 2005, and July 1, 2006.[18] Immigrants and their U.S.-born descendants are expected to provide most of the U.S. population gains in the decades ahead.[19]

The Census Bureau projects a U.S. population of 417 million in 2060, which is a 38% increase from 2007 (301.3 million).[20] However, the United Nations projects a U.S. population of 402 million in 2050, an increase of 32% from 2007.[21] In an official census report, it was reported that 54.4% (2,150,926 out of 3,953,593) of births in 2010, were non-Hispanic white. This represents an increase of 0.34% compared to the previous year, which was 54.06%.[22]

In 1900, when the U.S. population was 76 million, there were 66.8 million Whites in the United States, representing 88% of the total population,[26] 8.8 million African Americans, with about 90% of them still living in Southern states,[27] and slightly more than 500,000 Hispanics.[28]

Under the law, the Immigration and Nationality Act of 1965,[29] the number of first-generation immigrants living in the United States has increased,[30] from 9.6 million in 1970 to about 38 million in 2007.[31] Around a million people legally immigrated to the United States per year in the 1990s, up from 250,000 per year in the 1950s.[32] In 2009, 37% of immigrants originated in Asia, 42% in North America, and 11% in Africa.[33]

In 1900, non-Hispanic whites comprised almost 97% of the population of the 10 largest American cities.[34] By 2006, non-Hispanic whites had dwindled to a minority in 35 of the nation's 50 largest cities.[35] The Census Bureau reported that minorities (including Hispanic whites) made up 50.4% of the children born in the U.S. between July 2010 and July 2011,[36] compared to 37% in 1990.[37]

In 2010 the state with the lowest fertility rate was Rhode Island, with 1,630.5 children per thousand women, while Utah had the greatest rate with 2,449.0 children per thousand women.[38] This correlates with the ages of the states' populations: Rhode Island has the ninth-oldest median age in the US—39.2—while Utah has the youngest—29.0.[39]

The United States Census Bureau publishes a popular "dot" or "nighttime" map showing population distribution at a resolution of 7,500 people,[43] as well as complete listings of population density by place name.[44]

Each of the racial categories includes people who identify their ethnicity as Hispanic or Latino.[49] U.S. federal law defines Hispanic or Latino as "those who classify themselves in one of the specific Hispanic or Latino categories listed on the Census 2000 or ACS questionnaire"—Mexican", "Puerto Rican", or "Cuban"—as well as those who indicate that they are "other Spanish, Hispanic, or Latino.""[50]

Persons whose ethnicity is identified as Hispanic or Latino may be of any race.

The total population of Hispanic and Latino Americans comprised 50.5 million or 16.3% of the national total in 2010.

The 2000 U.S. Census counted same-sex couples in an oblique way; asking the sex and the relationship to the "main householder", whose sex was also asked. One organization specializing in analyzing gay demographic data reported, based on this count in the 2000 census and in the 2000 supplementary survey, that same-sex couples comprised between 0.99% and 1.13% of U.S. couples in 2000.[55] A 2006 report issued by The Williams Institute on Sexual Orientation concluded that the number of same-sex couples in the U.S. grew from 2000 to 2005, from nearly 600,000 couples in 2000 to almost 777,000 in 2005. 4.1% of Americans aged 18–45 identify as gay, lesbian, or bisexual[56]

A 2011 report by the Institute estimated that 4 million adults identify as gay or lesbian, representing 1.7% of the population over 18. A spokesperson said that, until recently, few studies have tried to eliminate people who had occasionally undertaken homosexual behavior or entertained homosexual thoughts, from people who identified as lesbian or gay.[57] (Older estimates have varied depending on methodology and timing; see Demographics of sexual orientation for a list of studies.) The American Community Survey from the 2000 U.S. Census estimated 776,943 same-sex couple households in the country as a whole, representing about 0.5% of the population.[56]

A report by the U.S. Census Bureau projects a decrease in the ratio of Whites between 2010 and 2050, from 79.5% to 74.0%.[60] At the same time, Non-Hispanic Whites are projected to no longer make up a majority of the population by 2042, but will remain the largest single ethnic group. In 2050 they will compose 46.3% of the population. Non-Hispanic whites made up 85% of the population in 1960.[61]

The report foresees the Hispanic or Latino population rising from 16% today to 30% by 2050, the African American percentage barely rising from 12.9% to 13.1%, and Asian Americans upping their 4.6% share to 7.8%. The United States had a population of 310 million people in October 2010, and is projected to reach 400 million by 2039 and 439 million in 2050.[20][62][63][64] It is further projected that 82% of the increase in population from 2005 to 2050 will be due to immigrants and their children.[65]

Of the nation's children in 2050, 62% are expected to be of a minority ethnicity, up from 44% today. Approximately 39% are projected to be Hispanic or Latino (up from 22% in 2008), and 38% are projected to be single-race, non-Hispanic Whites (down from 56% in 2008).[66]

In 2008, the U.S. Census Bureau projected future censuses as follows:[20]

The table below is based mainly on selected data as reported to the United States Census Bureau. It only includes the voluntary self-reported membership of religious bodies with 750,000 or more. The definition of a member is determined by each religious body.[67] In 2004[update], the US census bureau reported that about 13% of the population did not identify itself as a member of any religion.[68][clarification needed] In a Pew Research Survey performed in 2012, Americans without a religion (atheists, agnostics, nothing in particular, etc.) surpassed Evangelical Protestant Americans with almost 20% of Americans being nonreligious. If this current growth rate continues, by 2050, around 51% of Americans will not have a religion.[69] A survey conducted in 2014 by the same organization indicated that the percentage of Americans unaffiliated with a religion rose to nearly 23% of the population, up from 16% in 2007.[70]

Adult respondents were asked the open-ended question, "What is your religion, if any?". Interviewers did not prompt or offer a suggested list of potential answers. The religion of the spouse or partner was also asked. If the initial answer was "Protestant" or "Christian" further questions were asked to probe which particular denomination. About one-third of the sample was asked more detailed demographic questions.

Religious Self-Identification of the U.S. Adult Population: 1990, 2001, 2008[73]
Figures are not adjusted for refusals to reply; investigators suspect refusals are possibly more representative of "no religion" than any other group.

In 2006, the median household income in the United States was around $46,326. Household and personal income depends on variables such as race, number of income earners, educational attainment and marital status.

Social classes in the United States lack distinct boundaries and may overlap. Even their existence (when distinguished from economic strata) is controversial. The following table provides a summary of some prominent academic theories on the stratification of American society:

In 2010, the average man weighed 194.7 pounds (88.3 kg); the average woman 164.7 pounds (74.7 kg).[75] The height of an American man was 5 feet 9 inches (1.75 m)[76] and woman 5 feet 3.8 inches (1.621 m)[77] The average BMI is 27.3 for males (overweight) and 28.5 for females (overweight).[78]

As of 2012, an estimated 26% of the population is obese,[79] 21% smoke,[80] and 11% have diabetes.[81]

A nationwide study in 2010 indicated that 19.5% of teens, aged 12–19, have developed "slight" hearing loss. "Slight" was defined as an inability to hear at 16 to 24 decibels.[82]

A study by William Strauss and Neil Howe, in their books Generations and Fourth Turning, looked at generational similarities and differences going back to the 15th century and concluded that over 80-year spans, generations proceed through four stages of about 20 years each.

A definitive recent study of US generational cohorts was done by Schuman and Scott (2012) in which a broad sample of adults of all ages was asked, "What world events are especially important to you?"[84] They found that 33 events were mentioned with great frequency. When the ages of the respondents were correlated with the expressed importance rankings, seven (some put 8 or 9) distinct cohorts became evident.

Today the following descriptors are frequently used for these cohorts (alive in 2000–10):

G.I. Generation—born from approximately 1901 to 1924 (depression cohort who fought and won World War II).

Baby Boomers—commentators use birth dates ranging from the early 1940s to the early 1960s.

Generation X—commentators use beginning birth dates from the early 1960s to the early 1980s.[87]

In the U.S., some called Generation Xers the "baby bust" generation because of the drop in the birth rate following the baby boom.[88] The drop in fertility rates in America began in the late 1950s. But according to authors and demographers William Strauss and Neil Howe (who use 1961 to 1981 for Gen X birth years), there are approximately 88.5 million Gen Xers in the U.S. today.[89][90]

Subdivided groups are present when peak boom years or inverted peak bust years are present, and may be represented by a normal or inverted bell-shaped curve (rather than a straight curve). The boom subdivided cohorts may be considered as "pre-peak" (including peak year) and "post-peak". The year 1957 was the baby boom peak with 4.3 million births and 122.7 fertility rate. Although post-peak births (such as trailing edge boomers) are in decline, and sometimes referred to as a "bust", there are still a relatively large number of births. The dearth-in-birth bust cohorts include those up to the valley birth year, and those including and beyond, leading up to the subsequent normal birth rate. The Baby boom began around 1943 to 1946.[citation needed]

From the decline in U.S. birth rates starting in 1958 and the introduction of the birth-control pill in 1960, the Baby Boomer normal distribution curve is negatively skewed. The trend in birth rates from 1958 to 1961 show a tendency to end late in the decade at approximately 1969, thus returning to pre-WWII levels, with 12 years of rising and 12 years of declining birth rates. Pre-war birth rates were defined as anywhere between 1939 and 1941 by demographers such as the Taeuber's, Philip M. Hauser and William Fielding Ogburn.[94]

In 2009, Time magazine reported that 40% of births were to unmarried women.[98] The following is a breakdown by race for unwed births: 17% Asian, 29% White, 53% Hispanics, 66% Native Americans, and 72% African American.[99]

13% of the population was foreign-born in 2009 a rise of 350% since 1970 when foreign-born people accounted for 3.7% of the population,[104]including 11.2 million undocumented aliens,[105] 80% of whom come from Latin America.[106] Latin America is the largest region-of-birth group, accounting for over half (53%) of all foreign born population in US,[107] and thus is also the largest source of both legal and illegal immigration to US.[108] In 2011, there are 18.1 million naturalized citizens in USA, accounting for 45% of the foreign-born population (40.4 million) and 6 percent of the total US population at the time,[109] and around 680,000 legal immigrants are naturalized annually.[110]

4.32 people migrate per 1,000 population, estimated in 2010.[citation needed]

As of July 2015[update], the U.S. unemployment rate was 5.3 percent (U3 Rate).[112]

As of July 2014[update], the U.S. unemployment rate was 6.2 percent (U3 Rate).[113]

As of February 2014[update], the U6 unemployment rate is 14.9 percent.[114] The U6 unemployment rate counts not only people without work seeking full-time employment (the more familiar U-3 rate), but also counts "marginally attached workers and those working part-time for economic reasons." Note that some of these part-time workers counted as employed by U-3 could be working as little as an hour a week. And the "marginally attached workers" include those who have gotten discouraged and stopped looking, but still want to work. The age considered for this calculation is 16 years and over.[115]